This invention relates generally to printing presses, and particularly to apparatus for supplying paper to printing presses of the type adapted to print a plurality of independent paper webs simultaneously.
Machines used in printing newspapers typically include a plurality of presses for simultaneously printing several individual sheets with means provided for simultaneously supplying independent webs of paper to each press for a printing run. The supply means typically includes a set of roll stands upon which independent rolls of paper may be rotatably mounted, and a set of rollers for guiding the webs of paper from each roll to one of the presses.
In performing a press run it is most important that the presses be operated without interruption through the printing of a single edition. A stoppage in the middle of a run creates risks of plate contamination by upsetting the balance of inks and other fluids. Edition deadline may also fail to be met and labor cost increased.
A principle cause of early press shutdowns is premature consumption of paper from one of the supply rolls. Such premature exhaustion of paper necessitates a halting of all the presses. When this is achieved a new roll of paper is mounted to the vacant, or nearly vacant, roll stand and secured to the trailing edge of the consumed roll by paste or tape. Furthermore, even where a new, full roll of paper is mounted to a vacant roll stand it frequently occurs that the paper remaining on yet another of the roll stands is insufficient to complete the run. This in turn necessitates yet another premature termination of the run.
The just described problem of early press shutdown occasioned by premature consumption of paper was previously recognized in U.S. Pat. No. 1,961,685. This patent, as well as others, has provided various approaches towards solving this problem of early press shutdown. Perhaps the most successful approach to date has been the provision of rewind apparatuses for adding paper to partially consumed rolls in advance of the press run to insure supply sufficiency. To accomplish this apparatuses have been provided for driving one or more of the rolls in a direction opposite that of its normal rotation in feeding paper to a press. Unfortunately, these machines have been relatively bulky and expensive, and difficult to connect and disconnect with speed and facility.
Accordingly, it is a general object of the present invention to provide improved apparatuses for supplying paper to printing presses.
More particularly, it is an object of the invention to provide improved apparatuses for supplying paper to printing presses of the type adopted to print a plurality of independent paper webs simultaneously.
Another object of the invention is to provide improved apparatuses for adding paper to partially consumed rolls of paper mounted on printing press supply roll stands.
Yet another object of the invention is to provide apparatuses for supplying paper from a plurality of roll stands to a plurality of individual press units without premature consumption of paper from any one roll stand, and which apparatuses are relatively easy to operate, efficient, inexpensive, light in weight and small in size.